ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration of Risk (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) manufacturer item	Dec. 31, 2018 USD ($)
Concentration Risk [Line Items]
Accounts receivable related to product sales	$ 38,400	$ 23,100
Accounts receivable, net	42,744	37,211
Receivables from Collegium
Concentration Risk [Line Items]
Accounts receivable, net	4,104	$ 14,011
Collegium Pharmaceutical Inc \| Commercialization Agreement
Concentration Risk [Line Items]
Prepaid and other current assets	1,500
Collegium Pharmaceutical Inc \| Commercialization Agreement \| Receivables from Collegium
Concentration Risk [Line Items]
Accounts receivable, net	$ 4,100
Customer concentration risk \| Consolidated revenue
Concentration Risk [Line Items]
Number of major distributors \| item	3
Gralise \| Supplier concentration risk
Concentration Risk [Line Items]
Number of third-party contract manufacturers for the supply of gabapentin \| manufacturer	1

Accounts Receivable Related To Product Sales

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- Definition

Concentration Risk, Number Of Third-Party Contract Manufacturers

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Represents the number of distributors of the entity.

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Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

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